PS36, Petropavlovsk-Kamchatskiy, Russian Federation

PS36, Petropavlovsk-Kamchatskiy, Russian Federation

Thumbnail profile: Kamchatka Peninsula

Located on a peninsula in far eastern Russia, Petropavlovsk-Kamchatskiy is one of the most geologically and meteorologically active regions in the world. Surrounded by volcanoes, volcanic eruptions are common and the area is buffeted by hurricane-force winds.

Kamchatka peninsula is nine time zones east of Moscow. It is huge: its total area of more than 470,000 km² makes it as large as Germany, Switzerland and Austria combined. But it is very sparsely populated: with only 400,000 inhabitants, its entire population is about equal to the number of residents of the single small Swiss city of Geneva.

Weather, Geology and Topography

The average annual temperature is -3°C while absolute minimal winter temperatures can fall to -53°C. Winters are long, cold and snowy (i.e. there is snow cover usually from October to June) while “summers” are equally cold, rainy and windy, sometimes with hurricane-strength winds.

Kamchatka’s position on the northwestern edge of the Pacific “ring of fire” means that it is not only the site of multiple volcanoes—29 of the 160 total in this region are active—it also sits atop the area where the Pacific Plate collides with other tectonic plates, producing frequent earthquakes. In fact, this peninsula, created by the northwesterly movement of the Pacific plate, is one of the world's classic examples of large scale subduction of an oceanic plate at a very active convergent boundary. The region is therefore of special interest for seismic measurements.

In geology, a subduction zone is an area on Earth where two tectonic plates meet and move towards one another, with one sliding underneath the other and moving down into the mantle, at rates typically measured in centimeters per year. In Kamchatka, the result is a chain of very large strato- or composite volcanoes with dark, fine-grained volcanic rock. In typical plate boundary style, the volcanic zone includes some more explosive, caldera-forming volcanoes (i.e. a volcanic feature formed by the collapse of a volcano into itself, making it a large, special form of volcanic crater) that produce more mildly explosive cinder cones and shield volcanoes.

A long history of plate convergence has created parallel volcanic mountain belts that now form the core of the Kamchatka peninsula. The northwesterly movement of the Pacific Ocean plate continues at a rate of about 80 mm per year and causes this active subduction zone beneath Kamchatka.

Petropavlovsk

Shrouded in military confidentiality until the early 1990s, Kamchatka was closed, not only to foreigners but even to most Russians, due to its strategic military importance and the presence of military bases on the peninsula. For example, it is home to the Russian Pacific Submarine Fleet, as well as the site of several airbases and a testing ground for intercontinental ballistic missiles.

The “frontier town” of Petropavlovsk-Kamchatsky serves as the administrative, industrial, scientific and cultural center of Kamchatka Krai (Russia) and is by far the largest town in extreme northeastern Russia.

The city is situated on high hills surrounded by so many volcanoes that the horizon cannot be seen clearly from any point since mountains and volcanoes encircle it.

Russia hosts the second highest number of IMS facilities of any CTBT Member State after the United States: these include five other primary and 13 auxiliary seismic stations, four infrasound stations, 8 radionuclide stations and one radionuclide laboratory.

Station Location

PS36 is located in the valley of the Plotnikov River about 100 km north of the town. It is notable that, besides this primary seismic station, Petropavlovsk-Kamchatskiy also hosts two other IMS stations: infrasound station IS44 and radionuclide station RN60.

According to the IMS 2006 Certification Report, this particular area of the Kamchatka peninsula is characterized by the “frequent occurrence of hurricanes, earthquakes, forceful continuous blizzards, intense precipitation, avalanches and tsunamis in the coastal regions”.

In short, an inviting destination - at least for IMS experts: The low interference of human activity with seismic and infrasound measuring and its exposure to strong winds that can carry both low-frequency soundwaves and airborne radioactive particles from long distances make Petropavlovsk-Kamchatskiy an ideal location for three of the IMS’s verification technologies.

Equipment consists of seismometers, installed at a depth of 50 metres, and digitizers installed inside vaults (i.e. a reinforced room or compartment), a power distribution network backed up by a diesel generator, buried and aerial power lines, a Global Positioning System (GPS) antennae with lightning protection, an intra-array communication sub-system, alarm units with visuals and audible alarms to detect unauthorized access to the array elements, voltage alteration and/or temperature changes, and data acquisition and processing equipment at the CRF. Equipment in the CRF, as well as the power and communication sub-systems, are shared with the geographically co-located infrasound station.

The station has performed with the required data availability (average 98%) and the data have been used successfully in International Data Centre (IDC) processing. This station was therefore certified on 16 November 2006 and has been monitoring seismic activity and transmitting data continuously ever since.